JP2010517872A - Method for operating a vehicle drive train - Google Patents

Abstract

  The present invention is directed to one manual transmission and one end of a single group or multi-group structure for shifting gears with one internal combustion engine, one engine clutch, one electric machine and synchronous and / or asynchronous transmission elements. The present invention relates to a method for operating a vehicle drive train having an arrangement including at least a reduction gear and an attached control mechanism for controlling a shift process, a drive train, and a vehicle equipped with such a drive train. In order to expand the possibilities of function with this arrangement, the electric machine is used as a synchronization means, as a synchronization auxiliary body, or at least as a transmission auxiliary body during the shifting process in a manual transmission, taking into account changes in the rotational direction of the transmission shaft Is done.

Description

  The present invention relates to a method for operating a vehicle drive train as described in the preamble of claim 1, a drive train as described in the preamble of claim 10, and a vehicle equipped with such a drive train.

  It is already known to use electrical machines in vehicle drivetrains, in particular in automobiles. The electric machine includes, for example, a drive assembly, an auxiliary drive device for an all-wheel drive device, a stage drive device for realizing a reverse stage, a starter motor for an internal combustion engine, a starting auxiliary body, an electromagnetic retarder, a lubricating oil, and the like in a hybrid system Various functions such as a pump driving device for supplying cooling oil or a generator in the regenerative mechanism can be performed. In addition, synchronize within the manual transmission to at least partially eliminate the usual synchronizer with friction elements, thus saving manufacturing costs and mounting space, shortening shift times and improving shift comfort It is known to use an electric machine to do this.

  Such a drive train of an automobile and a method for operating it are known from DE 10 2005007966 A1. There, an electric motor is provided in the drivetrain arrangement consisting of an internal combustion engine-engine clutch-electric motor-manual transmission input shaft / manual transmission-final decelerator in the direction of power flow. It can be used to synchronize the transmission within the transmission. For example, when the engine clutch is released and the transmission is in the neutral position, the electric motor can change the transmission shaft and the speed before each selected target stage is shifted. Synchronous rotation speed is provided between the gears to be driven. This publication further states that in the case of an asynchronous multi-group transmission, the synchronization can be performed by repeatedly realizing the synchronous rotational speed with an electric motor. But no further explanation on this point can be found in this publication.

  Furthermore, it is known to use electric machines in double clutch transmissions. The counter shaft structure type automatic double clutch transmission described in the applicant's unpublished German patent application DE102006036758.8 is provided with a group of step gear sets and a starting element, respectively. Two transmission input shafts and a speed change element formed as an asynchronous clutch. Both starting elements, implemented as a double clutch unit, are formed as an asynchronous engine clutch in the form of a pawl. Both starting elements are connected to input shafts respectively provided on the transmission side, and can be alternately connected to the crankshaft of the internal combustion engine on the drive side. Either an electric machine whose rotor meshes with the highest stage drive gear of each stage group via a pinion or a common electric machine that can be operatively coupled to the stage gears alternately on both input shafts. It is attached.

  The electric machine is effective as a starting and synchronizing means. During the starting process, the vehicle is first accelerated by the electric machine after the start stage clutch is engaged until the engine clutch can be engaged when the synchronous rotational speed of the drive shaft is reached. At the stage switching, the target stage engine clutch is first released, and the target stage input shaft is accelerated by the attached electric machine until the target stage stage clutch can be engaged when the synchronous rotational speed is reached, then The electric machine temporarily takes on the increasing load, the old engine clutch is released, the old gear is released, and the prime mover is controlled by the controller to a new synchronous speed, and then the target engine clutch. Can be engaged. Further, depending on the at least one electric machine, the reverse gear can be realized by operatively coupling with the forward start gear set by reversing the rotor rotation direction of the electric machine.

  In other double-clutch transmissions known from DE 10133695 A1 DE 1,133,695 A1, at least one transmission input shaft can be coupled to an electric machine. During the shifting process, the transmission input shaft can be accelerated by an electric machine for synchronization, or can be decelerated to the lowest stage, especially during a downshift. In doing so, the electric machine can cooperate with the existing synchronization mechanism.

  The above publications disclose the various possibilities of using electric machines in a vehicle-drivetrain for synchronization, particularly in conventional manual transmissions and double clutch transmissions, and address the problems underlying them. Can be fully fulfilled. As a disadvantage, those skilled in the art find, or at least inadequately, find in them instructions on how to apply an electric machine in problematic and / or relatively complex shifting processes.

German Patent Application Publication DE102005007966A1 German Patent Application Publication DE10133695A1

  In view of the above, it is an object of the present invention to specify a method for operating a drive train in a vehicle, to improve the drive train for that purpose, and to attach to the drive train, in particular for synchronization during the shifting process. It is to improve and expand the functional possibilities of the machined electrical machine.

  The solution to this problem will be apparent from the features of the independent claims, and advantageous configurations and aspects of the invention can be read from the appended dependent claims.

  The basis of the present invention is that, on the one hand, an irregular rotation direction of the transmission shaft in the manual transmission can occur, making the shifting process impossible or at least difficult or slowing down, while on the other hand the electrical in the drive train. The machine can be actuated in both directions of rotation by corresponding drives, the electrical machine can also adjust the direction of rotation of this transmission shaft and / or another transmission shaft that can be operatively coupled to this transmission shaft; It is recognized that this makes it possible to achieve the desired shift for the first time in a specific operating situation, or at least improve the synchronous shift.

  Accordingly, the present invention provides one manual transmission and one single-group or multi-group structure for shifting gears with one internal combustion engine, one engine clutch, one electric machine and synchronous and / or asynchronous transmission elements. We start with a method for operating a vehicle drive train with an arrangement comprising at least a final reduction gear and an attached control mechanism for controlling the shifting process.

  In order to solve this problem, according to the present invention, an electric machine is used as a synchronization means, a synchronization auxiliary body, or at least as a transmission auxiliary body during a shifting process in a manual transmission, and changes in the rotational direction of the transmission shaft are taken into account. .

  The present invention further provides one manual transmission and one single-group or multi-group structure for shifting gears with one internal combustion engine, one engine clutch, one electric machine and synchronous and / or asynchronous transmission elements. The vehicle starts with a vehicle drive train that includes at least a final reduction gear and a control mechanism attached to control the shifting process. For this reason, according to the present invention, in this drive train, the electric machine can be correspondingly driven as a synchronizing means during the shifting process, as a synchronizing auxiliary body, or at least as a shifting auxiliary body when the rotation direction of the transmission shaft or shafts changes. It can be operatively connected to each transmission shaft to be added on the basis of a change in the rotational direction through the provided non-positive coupling means.

  This drive train is particularly well suited for carrying out the method according to the invention in the associated vehicle.

  The method advantageously provides an enhancement in the electrical machine for shifting in a manual transmission in a vehicle drive train. Basically, the method consists of a single group or multiple clutches comprising a single clutch or a double clutch and one or more electric machines which have a motor function and possibly a generator function and can be suitably driven via a control mechanism. Suitable for all kinds of manual transmission with group structure style.

  In a particularly advantageous application of the method, if an undesired vehicle coasting causes a change in the rotational direction of the transmission output shaft, contrary to the selected step or travel direction, first the old one to be correlated with the transmission output shaft. The direction of rotation of at least one further transmission shaft operating in the direction of rotation can be assimilated by the electric machine to the direction of rotation of the transmission output shaft.

  In this situation, during off-road applications, the vehicle runs on a steep slope and moves backward, while the manual transmission is in the neutral position during the shift and the transmission output shaft coupled to the drive wheels changes its direction of rotation. It happens relatively frequently when changing. A situation comparable to the starting process, particularly in heavy commercial vehicles, is also described in the German patent application DE102006030157.9, which has not been previously published by the applicant.

  In a manual transmission having a synchronization mechanism, a change in the rotational direction of the transmission output shaft may make it difficult to fit the steps, and at least increase the load on the synchronization member. Rather, in a transmission without a synchronization mechanism, the stage gear to be shifted cannot be synchronized at all, and it is possible that the selected target stage cannot be fitted. As a result, the vehicle will first have to stop and continue to start or restart.

  On the other hand, if such an operating situation that is irregular per se is detected, the method according to the invention allows the electric machine to also reverse the direction of rotation of the axes to be correlated operating in the old direction for a very short time. Thus, synchronization that protects the member in the transmission including the synchronizing member is possible. Directly following this, the vehicle can then be controlled by engaging the engine clutch, and the rotational speed of the internal combustion engine is temporarily reduced so that at least the clutch load generated at that time is within the allowable range. As long as you stay, you can flip in the selected direction. In a transmission without a synchronization member, in such a situation, the electric machine could first enable gear shifting in this way without having to brake and stop the vehicle.

  Furthermore, the electric machine is particularly advantageous for synchronization in a multi-group transmission, for example in a three-group transmission with a single splitter group, a central main group and a rear range group. It can be used and driven for reversing the rotational direction of the shaft that operates in the old direction when the rotational direction changes. The basic structure of such a group of three transmissions-without an electric machine-is known, for example, from the applicant's previously unpublished German patent application DE 102006024370.6.

  Transmission synchronization by electric machines within the group occurs relatively quickly, and overall very short shift times are achieved, and even all groups can even omit the conventional synchronization mechanism, which saves money and installation space in particular. Acts to save money. Only one or two groups can be formed without a synchronization element, or an electric machine can be connected as an additional synchronization auxiliary in a fully synchronous transmission, for example, corresponding energization of the electric machine and rotor rotation during irregular rotation directions Thus, it is basically possible to reverse the direction of rotation of the shaft to be correlated with the transmission output shaft.

In the simplest case, a continuous shifting process can therefore be provided, in which the engine clutch is first released and the old gear is released to reduce the load, and then each individual group is shut off, Synchronized by the machine, reconnected, and finally the target clutch is engaged by engaging the engine clutch and increasing the load. The details of the three-group transmission are as follows:
-The engine clutch is released and the old gear is released to reduce the load.
-Splitters are shut off,
-The splitters are synchronized,
-Splitters are connected,
-The main group is cut off,
-The main group is synchronized,
-Main groups are connected,
-Range group is cut off,
-Ranges are synchronized,
-Range groups are connected,
-The target stage is engaged by engaging the engine clutch and increasing the load.

  Connection and disconnection of each transmission part means that each transmission part is connected to or released from a common drive train in terms of drive technology.

  When shifting with such a multi-group transmission, the shift direction can be divided within the group at the time of stage switching, i.e. downshift can be performed within one or more groups, whereas upshifts are separate. In order to achieve an efficient shift process with a particularly short shift time, a predetermined criterion is provided, and the electric / hydraulic / empty engine to be shifted with the engine clutch. It is particularly advantageous if the pressure-type transmission element and the electric machine are driven correspondingly via a transmission control device.

It can be provided as a meaningful criterion for the optimal gear shifting process related to this.
-The number of reversal of the transmission shaft rotation direction to be carried out by the electric machine,
The value of each speed range to be synchronized by the electric machine,
-The value of each rotation speed sudden change,
-The direction of each revolution
-The speed level itself,
It is.

  It is therefore advantageous to synchronize first the rotational speed changes where the rotational direction reversal occurs as little as possible and / or the synchronization range of the electric machine is as small as possible and / or as large as possible, ie the upshift stage is preferentially synchronized. The shifting process is performed such that synchronization is performed at a rotational speed level as low as possible and / or as low as possible.

  In addition, the engine clutch can be selectively fully or partially engaged or remain fully or partially engaged in a given synchronization, thereby increasing shifting comfort. Can do. This is particularly advantageous during upshifts, where the internal combustion engine is synchronized together by a non-positive / friction joint connection via a slipped or engaged engine clutch.

  In order to further improve the shift time, the continuous connection phase and the disconnection phase of the group of multi-group transmissions can be selectively separated from each other in one shift process or can be carried out partially in time.

  During the gear shifting process of such a manual transmission, the tip-to-tip position of the gear to be shifted may appear. Therefore, in order to prevent the power flow from being damaged in the manual transmission and to enhance the shift safety, the gear shift is preferably continued when the tooth tip-to-tooth position appears. That is, the electrical machine in that group of multi-group transmissions is continuously or variably driven and operated until the corresponding gears are normally meshed and the respective tip-to-tip positions are removed.

  In summary, according to the present invention, when shifting in a single-group or multi-group transmission during traveling, when rolling unintentionally forward or backward, or by engaging a starting stage during the starting process, at least 1 When two transmission shafts change their rotational direction, preferably the rotational direction of the shaft operating in the old direction is reversed by the electric machine to achieve traveling operation with special protection for the transmission and high shift safety Can do. The shifting process requires only a relatively short shifting time due to the rapid synchronization and the vehicle can be controlled by the engine clutch or the starting clutch during or immediately after the shifting.

  This method is hereinafter referred to as one two-stage splitter group (GV) in front of the counter shaft structure type and one two-stage range group after one three-stage central main group (HG) and the planetary structure type. For example, a multi-group transmission without a synchronous mechanism (or at least having an asynchronous main group) such as a known 12-speed transmission of the applicant's known “ZF-AS Tronic” class. Explained. It is well known to those skilled in the art to arrange such a transmission and its mode of operation, and an electric machine operable as an electric motor and generator in a drive train. Therefore, a detailed description of the transmission is omitted here, and only the exemplary shifting process and the change in the rotational direction of the transmission shaft for the method according to the present invention will be referred to in detail.

  For this reason, a shift process from the sixth forward speed as the old speed to the seventh forward speed as the target speed is assumed. A downshift occurs in the main group (HG) and the splitter group (GV), and an upshift occurs in the range group (GP).

Therefore, the stage switching from the sixth stage to the seventh stage can be performed according to the following three schemas in consideration of the above judgment criteria, starting from the range group to be upshifted, and the adjacent connection stage and cutoff stage are It can advantageously be carried out partly.
I. Shifting process:
1. The load is reduced by opening the engine clutch.
2. Range group GP:
i. Shut off.
ii. Synchronizing. Reduced electrical machine speed due to upshift.
iii. Connection.
3. Main group HG:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
iii. Connection.
4). Splitter group GV:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
iii. Connection.
5). Engage the engine clutch and increase the load. Due to the power flow, the rotational speed of the internal combustion engine temporarily decreases.

II. Shifting process:
1. The load is reduced by opening the engine clutch.
2. Range group GP:
i. Shut off.
ii. Synchronizing. Reduced electrical machine speed due to upshift.
iii. Connection.
3. Main group HG:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
4). Partially engage the engine clutch. The engine speed is reduced and synchronized.
5). Main group:
i. Connection.
6). Splitter group GV:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
iii. Connection.
7). Increase the load by engaging the rest of the engine clutch.

III. Shifting process:
1. The load is reduced by opening the engine clutch.
2. Range group GP:
i. Shut off.

Claims (12)

One manual transmission, one final reduction gear and one shift in a single-group or multi-group structure for shifting gears with one internal combustion engine, one engine clutch and one electric machine with synchronous and / or asynchronous transmission elements In a method for operating a vehicle drivetrain with an arrangement comprising at least one attached control mechanism for controlling a process,
A method in which an electric machine is used as a synchronization means, as a synchronization auxiliary body, or at least as a transmission auxiliary body during a shifting process in a manual transmission, and taking into account a change in the rotational direction of the transmission shaft.   2. A method according to claim 1, characterized in that the direction of rotation of the transmission shaft to be correlated initially operating in the same direction of rotation is assimilated by the electric machine.   When an undesired vehicle coasting causes a change in the rotational direction of the transmission output shaft to occur in the opposite of the selected step direction, first at least another transmission shaft operating in the old rotational direction to be correlated with the transmission output shaft The method according to claim 1 or 2, characterized in that the rotational direction is assimilated to the rotational direction of the transmission output shaft by an electric machine.   In the case of multi-group transmissions having at least some asynchronous transmission elements, the electric machine is used as a synchronization means for synchronizing the individual groups when controlling the transmission process, taking into account changes in the rotational direction of the transmission shaft. The method according to claim 1, characterized in that:   In the case of a multi-group transmission with asynchronous transmission elements, the stage change is carried out in a continuous transmission process, first the engine clutch is released and the old stage is released to reduce the load, and then each individual group is shut off individually. 5. The method according to claim 4, characterized in that it is synchronized by the electric machine and reconnected, and finally the target clutch is engaged by engaging the engine clutch and increasing the load. In the case of a three-group transmission having one splitter group at the front, one central main group and one range group at the rear,
a) releasing the engine clutch and releasing the old gear to reduce the load;
b) shutting off the splitter group;
c) synchronizing the splitters;
d) connecting the splitter groups;
e) blocking the main group;
f) synchronizing the main group;
g) connecting the main groups;
h) blocking the range group;
i) synchronizing the range group;
j) connecting the range groups;
k) engaging the engine clutch and increasing the load to engage the target stage;
6. A method according to claim 5, characterized in that the stage switching is performed in the above steps. In the case of a multi-group transmission capable of selectively upshifting and downshifting within the group at the stage switching, in order to determine the shift / synchronization process in the minimum time for the group,
a) Number of reversal of the transmission shaft rotation direction to be performed by the electric machine,
b) the value of each speed range to be synchronized by the electric machine,
c) The value of each rotational speed sudden change,
d) Direction of each rotational speed sudden change,
e) the speed level itself,
5. A method according to claim 4, characterized in that the above criteria are taken into account individually or in combination.   8. The engine clutch according to claim 1, wherein the engine clutch is selectively fully or partially engaged or remains fully or partially engaged in a given synchronization. The method according to item.   9. The continuous connection phase and the disconnection phase of a group of multi-group transmissions are selectively separated from each other in one shift process, or are performed partially overlapping in time. The method according to any one of the above.   The gear change continues when the tooth tip-to-tooth position occurs, and in that group of multi-group transmissions, the electric machine continues or is variable until the corresponding gear is normally engaged and each tooth tip-to-tooth position is removed. 10. A method according to any one of claims 4 to 9, characterized in that it is driven and actuated in an equation.   One manual transmission, one final reduction gear and one shift in a single-group or multi-group structure mode for shifting gears with synchronous and / or asynchronous transmission elements with one internal combustion engine, one engine clutch and one electric machine One or more shifts in a vehicle drive train for implementing the method according to any one of claims 1 to 10, in particular comprising at least one attached control mechanism for controlling the process When the direction of rotation of the axle changes, the electric machine can be driven correspondingly as a synchronizing means during the shifting process, as a synchronizing auxiliary, or at least as a shifting auxiliary, and via the provided non-positive coupling means A drive train characterized in that it can be operatively coupled to each transmission shaft to be added based on changes. A vehicle comprising a drive train according to claim 11 for carrying out the method according to any one of claims 1-10.
i. Synchronizing. Reduced electrical machine speed due to upshift.
iii. Connection.
3. Main group HG:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
iii. Connection.
4). Splitter group GV:
i. Shut off.
ii. Synchronizing. Increased electric machine speed due to downshift.
5). Partially engage the engine clutch. The engine speed is reduced and synchronized.
6). Splitters:
i. Connection.
7). Increase the load by engaging the rest of the engine clutch.